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采用固相反应法分别合成了铬掺杂二氧化钛(Cr-TiO2)及硫和铬共掺杂二氧化钛(S-Cr-TiO2)纳米材料。并用XRD、SEM、UV-Vis、XPS、N2吸附等技术对材料进行了物相结构表征,同时研究了材料对水溶苯胺蓝的可见光降解性能。结果表明,在S-Cr-TiO2纳米材料中,硫以阳离子S6+进入二氧化钛晶格或晶格间隙,铬以同晶取代方式占据TiO2晶格中Ti的位置,其晶型为锐钛矿型。硫、铬的共掺杂能有效地限制TiO2晶体的生长,其紫外-可见漫反射吸收光谱覆盖了可见光区并延伸到近红外区域。在25℃,pH 6.5条件下,所制得的S-Cr-TiO2光催化材料对水溶苯胺蓝的可见光降解具有良好的光催化活性,并服从一级反应动力学规律,120min内,水溶苯胺蓝分解率达到83.7%,其可见光降解速率常数分别是纯TiO2及Cr-TiO2的1.96倍和1.38倍。
Chromium-doped titanium dioxide (Cr-TiO2) and sulfur-chromium-co-doped titanium dioxide (S-Cr-TiO2) nanomaterials were synthesized by solid state reaction. The phase structure of the material was characterized by XRD, SEM, UV-Vis, XPS and N2 adsorption. At the same time, the visible light degradation of water-soluble aniline blue was studied. The results show that in the S-Cr-TiO2 nanomaterials, the sulfur enters the titanium dioxide lattice or the lattice interstice with the cation S6 +, and the chromium takes the isomorphous substitution occupying the Ti in the TiO2 crystal lattice with the anatase type. Sulfur, chromium co-doping can effectively limit the growth of TiO2 crystals, the UV-visible diffuse reflectance absorption spectrum covers the visible region and extends to the near-infrared region. Under 25 ℃, pH 6.5, the S-Cr-TiO2 photocatalytic material has good photocatalytic activity for visible light degradation of water-soluble aniline blue, and obeys the first-order kinetics. Within 120 minutes, the aqueous aniline blue The decomposition rate reached 83.7%. The visible light degradation rate constants were 1.96 times and 1.38 times that of pure TiO2 and Cr-TiO2 respectively.